Do you know what your cat's third eye lid looks like? The third eyelid is a white-ish, fleshy membrane that starts at the inside corner of the eye and can come up, across the eye completely or partially, hiding the eyeball, itself. Sometimes, this will give the appearance that the eye is rolled back.
The third eyelid will appear when a cat isn't feel well, in general, or there is an eye problem. If he seems to be squinting this eye or holding it closed or only open halfway, this would indicate a problem.
Due to his lethargy and unusual appearance of his eye, it would be advisable to have him evaluated in person by a vet, as soon as possible, for a definite diagnosis and treatment. You can bring him in first thing tomorrow morning, but if his symptoms seem to worsen, he doesn't want to eat at all, has trouble breathing, walking or eliminating, you can bring him to an ER vet center nearby, tonight.
I hope all will be well with Sir Smudge, The Rolly Polly and please let me know how he's doing and what the vet tells you. Thanks!
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